getent

Name Service Switch database query tool

TLDR

Look up a passwd entry by UID

$ getent passwd [1000]

List every entry in the group database

$ getent group

Show members of one group name

$ getent group [group_name]

Resolve a hostname via hosts (NSS)

$ getent hosts [hostname]

List known services from the services database

$ getent services

getent queries entries from administrative databases configured in the Name Service Switch (NSS), including local files, LDAP, NIS, and other sources. It provides a unified interface to look up users, groups, hosts, and other system information regardless of where the data is stored.Unlike directly reading files like /etc/passwd, getent returns results from all configured NSS sources, making it essential for systems using centralized authentication (LDAP, Active Directory, etc.).Without a key, getent lists all entries in the database. With a key, it returns only matching entries.

PARAMETERS

passwd

User account database (/etc/passwd and NSS sources)

group

Group database (/etc/group and NSS sources)

hosts

Hostname/IP resolution (like /etc/hosts, DNS)

services

Network services (/etc/services)

protocols

Network protocols (/etc/protocols)

networks

Network names and addresses

shadow

Shadow password entries (requires root)

aliases

Mail aliases

CONFIGURATION

/etc/nsswitch.conf

Name Service Switch configuration determining which sources to query for each database type.

INSTALL

sudo apt install libc-bin

sudo apk add musl-utils

nix profile install nixpkgs#getent

CAVEATS

The shadow database requires root privileges. Some databases may not support enumeration (listing all entries). Results depend on NSS configuration in /etc/nsswitch.conf.

HISTORY

getent has been part of the GNU C Library (glibc) since the implementation of the Name Service Switch in the early 1990s, providing a standard way to query system databases that may come from multiple sources.